Method and machine for packing a product in a flat tubular package

ABSTRACT

A method and machine for packing a group of cartons of cigarettes in a flat tubular package, whereby a first portion and a second portion of a suction gripping head respectively engage a first lateral wall of the flat tubular package, and a second lateral wall of the flat tubular package separated from the first lateral wall by a respective preformed fold line; a rotational movement is then generated between the first and second portion of the suction gripping head to rotate the first and second lateral wall engaged by the suction gripping head with respect to each other, and so convert the flat tubular package from the flat configuration to an open configuration; the group of cartons of cigarettes is then pushed inside the open tubular package, and the suction gripping head is moved to feed the open tubular package to a sealing station where the open tubular package is sealed.

TECHNICAL FIELD

The present invention relates to a method and to a machine for packing aproduct in a flat tubular package.

The present invention may be used to advantage on a cigarette cartonboxing machine, i.e. a machine for packing groups of cartons ofcigarettes in respective boxes, to which the following descriptionrefers purely by way of example.

BACKGROUND ART

Machines for boxing cartons of cigarettes currently comprise a unit forsupplying and opening flat tubular packages, and which receives a stackof flat tubular packages on a pallet, and feeds each flat tubularpackage to a respective seat on a conveyor, which feeds the tubularpackage along a straight packing path. Along the packing path, eachtubular package remains connected to the respective seat, and is fedthrough an opening station, where the tubular package is opened into aconfiguration suitable for receiving a respective group of cartons ofcigarettes; through an insertion station, where a respective group ofcartons of cigarettes is pushed inside the open tubular package; and,finally, through a sealing station, where the tubular package is sealedby gumming and folding the relative flaps.

Known boxing machines of the above type are fairly bulky, and, for useon the machine, require accurate positioning of the stack of flattubular packages, and therefore periodic assistance on the part of theoperator.

WO8900132 discloses a carton loading and closing machine comprising acarton opening mechanism adapted to remove a flat carton from a magazineto a park position, means for folding the side flaps at the bottom ofthe carton outwardly, means for loading product into carton through itsopen bottom, means for indexing the loaded carton forwardly over cammeans for folding the leading end flap under the product, trailing endflap closing means having a slot adapted to receive the trailing endflap and means for causing said trailing end flap to be folded to theclosed position as said folding means is moved transversely with respectto the stationary carton, and means for closing the side flaps and thetop flaps of the carton.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide a method and amachine for packing a product in a flat tubular package, designed toeliminate the aforementioned drawbacks, and which, in particular, isstraightforward and cheap to implement.

According to the present invention, there is provided a method ofpacking a product in a flat tubular package as recited by Claim 1.

According to the present invention, there is provided a machine forpacking a product in a flat tubular package as recited by Claim 15.

BRIEF DESCRIPTION OF THE DRAWINGS

A non-limiting embodiment of the present invention will be described byway of example with reference to the accompanying drawings, in which:

FIG. 1 shows a schematic plan view, with parts removed for clarity, of acigarette carton boxing machine in accordance with the presentinvention;

FIG. 2 shows a front view, with parts removed for clarity, of the FIG. 1boxing machine;

FIGS. 3, 4 and 5 show, schematically, an operating sequence of agripping head of the FIG. 1 boxing machine.

BEST MODE FOR CARRYING OUT THE INVENTION

Number 1 in FIG. 1 indicates as a whole a boxing machine for boxinggroups 2 of cartons of cigarettes, and which inserts each group 2 ofcartons of cigarettes inside a respective tubular package 3 having twomajor lateral walls 4; and two minor lateral walls 5, each connected onone side to one major lateral wall 4, and on the other side to the othermajor lateral wall 4, by respective preformed fold lines 6. Morespecifically, each major lateral wall 4 has two flaps 7, and each minorlateral wall 5 has two flaps 8; and, once group 2 of cartons ofcigarettes is inserted inside a respective tubular package 3, therelative flaps 7 and 8 are folded one on top of another to define twoend walls 9. Once flaps 7 and 8 are folded, the shape of tubular package3 is preferably stabilized by applying respective lengths of adhesivetape 10 to both end walls 9.

Boxing machine 1 comprises a pickup station 11, which houses a pallet 12supporting a stack 13 of flat tubular packages 3, i.e. tubular packages3 pressed into a flat configuration and lying in a horizontal plane.

Boxing machine 1 also comprises a suction gripping head 14 for engagingthe free major lateral wall 4 and the free minor lateral wall 5 of thetop flat tubular package 3 in stack 13; and an actuating device 15supporting gripping head 14, and for moving gripping head 14 from pickupstation 11 to a sealing station 16 via an intermediate feed station 17.

As shown in FIG. 2, actuating device 15 moves gripping head 14 with fourdegrees of freedom comprising three translatory movements in threeperpendicular directions 18, 19, 20 (18 shown in FIG. 1); and arotational movement about a vertical axis 21 perpendicular to thehorizontal plane of flat tubular packages 3 in stack 13. Morespecifically, actuating device 15 comprises a guide 22 supported at theends by two powered carriages 23, which run along respective guides 24to move guide 22 in horizontal direction 18 perpendicular to the FIG. 2plane. A powered carriage 25 runs along guide 22, and supports a linearactuator 26 moved by carriage 25 in horizontal direction 19. Linearactuator 26 comprises a member 27 integral with carriage 25; and amember 28 supporting gripping head 14 and moved with respect to member27 in vertical direction 20; and a powered articulated joint 29 isinterposed between member 28 and gripping head 14 to rotate grippinghead 14 about vertical axis 21.

Actuating device 15 therefore maintains suction gripping head 14horizontal at all times, and therefore parallel to the plane of flattubular packages 3.

Suction gripping head 14 comprises a suction portion 30 for engaging amajor lateral wall 4 of a tubular package 3, and a suction portion 31,which engages a minor lateral wall 5 of a tubular package 3, is hingedto suction portion 30, and is rotated, with respect to suction portion30, about a horizontal axis 32 by an actuating device 33 carried bysuction gripping head 14. More specifically, suction portions 30 and 31of gripping head 14 have respective known suction cups 34 made ofdeformable elastic material and connectable internally to a knownsuction source (not shown).

As shown in FIGS. 3, 4 and 5, the axis of rotation 32 between portions30 and 31 coincides substantially (i.e. exactly or very nearly) with thefold line 6 between lateral walls 4 and 5 engaged by gripping head 14.In a further embodiment not shown, the axis of rotation 32 betweenportions 30 and 31 does not coincide with the fold line 6 betweenlateral walls 4 and 5 engaged by gripping head 14, and suction cups 34of portion 30 are fitted to portion 30 so as to slide in a directionperpendicular to axis of rotation 32.

As shown in FIG. 2, suction gripping head 14 comprises a known opticalsensor 35 for determining the exact position of the top flat tubularpackage 3 in stack 13 before the flat tubular package 3 is engaged; anda known control unit (not shown) is provided to control actuating device15 supporting suction gripping head 14, so as to adapt the position ofsuction gripping head 14 to the exact position reading of flat tubularpackage 3, and engage the flat tubular package 3 in accordance with agiven mutual arrangement. Actuating device 15 thus provides forcorrecting any errors in the position of flat tubular packages 3 instack 13.

As shown in FIGS. 1 and 2, pickup station 11 is located beneath feedstation 17, where an insertion device 36 inserts a group 2 of cartons ofcigarettes inside a respective open tubular package 3 supported bysuction gripping head 14. Insertion device 36 comprises a belt conveyor37 for feeding groups 2 of cartons of cigarettes successively intoalignment with the open tubular package 3 at feed station 17; and apusher 38 for pushing group 2 of cartons of cigarettes inside the opentubular package 3. Fixed sections 39 are preferably provided betweenconveyor 37 and tubular package 3 to assist insertion of group 2 ofcartons of cigarettes inside respective open tubular package 3, and inparticular to keep flaps 7 and 8 of tubular package 3 clear of the pathof group 2 of cartons of cigarettes.

Sealing station 16 is located alongside and on a level with feed station17, and comprises a belt conveyor 40, in turn comprising two suctionbelts 41 looped about respective powered end pulleys 42 to define achannel 43 for receiving and conveying an open tubular package 3containing a respective group 2 of cartons of cigarettes. Conveyor 40 ishinged to rotate, under control of a known motor (not shown) and about ahorizontal axis 44, between a horizontal position (shown by thecontinuous line in FIG. 2) wherein conveyor 40 feeds a tubular package 3along a horizontal path inside channel 43, and a vertical position(shown by the dash line in FIG. 2) wherein conveyor 40 feeds a tubularpackage 3 along a vertical path inside channel 43.

In the horizontal position, conveyor 40 is connected to two knownsealing devices 45 located on opposite sides of conveyor 40, and whichfold down, one on top of another, the flaps 7 and 8 of a tubular package3 travelling inside channel 43, and apply respective lengths of adhesivetape 10 to the folded flaps 7 and 8 to define end walls 9 of tubularpackage 3.

In the vertical position, conveyor 40 is aligned with a follow-up beltconveyor 46, which receives the sealed tubular packages 3 from conveyor40, and feeds tubular packages 3 to a known output station (not shown)of boxing machine 1.

In an alternative embodiment not shown, conveyor 40 is fixed, andconveyor 46 is aligned horizontally with conveyor 40. In a furtherembodiment not shown, sealing devices 45 are located at feed station 17to seal the tubular package 3 at feed station 17, as soon as arespective group 2 of cartons of cigarettes is inserted by insertiondevice 36 inside the open tubular package 3.

Operation of boxing machine 1 will now be described with reference tothe top flat tubular package 3 in stack 13, and to a respective group 2of cartons of cigarettes.

To begin with, actuating device 15 moves suction gripping head 14 overto pickup station 11 to engage the flat tubular package 3, and so thatsuction portion 30 of suction gripping head 14 engages major lateralwall 4 of flat tubular package 3, and suction portion 31 of suctiongripping head 14 engages minor lateral wall 5 of flat tubular package 3.More specifically, actuating devices 15 moves suction gripping head 14over to roughly the estimated position of flat tubular package 3 (i.e.the position occupied in normal conditions); by means of optical sensor35, suction gripping head 14 then determines the real position of flattubular package 3; and, on the basis of the real-position reading offlat tubular package 3, actuating device 15 is operated to adapt theposition of suction gripping head 14 to the real position of flattubular package 3, and so enable gripping head 14 to engage flat tubularpackage 3 in accordance with a given mutual arrangement.

Actuating device 15 then moves suction gripping head 14, together withflat tubular package 3, from pickup station 11 to feed station 17. And,as it is being transferred from pickup station 11 to feed station 17,tubular package 3 is converted from the flat configuration to an openconfiguration by rotating portion 31 of suction gripping head 14 ninetydegrees about axis 32 with respect to portion 30 of suction grippinghead 14.

The relative rotation between portions 30 and 31 of suction grippinghead 14 is shown in FIGS. 3, 4 and 5, which clearly show how 90°rotation about axis 32 of portion 31 with respect to portion 30 producesa like rotation, about respective fold line 6, of minor lateral wall 5,engaged by portion 31, with respect to major lateral wall 4 engaged byportion 30; which 90° rotation between lateral walls 4 and 5 engaged bygripping head 14 causes tubular package 3 to pass from the flat to theopen configuration. Since the axis of rotation 32 between portions 30and 31 substantially coincides with fold line 6 between lateral walls 4and 5 engaged by gripping head 14, all the points on portion 31 performthe same movement as the corresponding points on minor lateral wall 5,and no translatory movement is generated between suction cups 34 ofportion 31 and minor lateral wall 5. Conversely, if the axis of rotation32 between portions 30 and 31 does not coincide with fold line 6 betweenlateral walls 4 and 5 engaged by gripping head 14, the points on portion31 perform a different movement with respect to the corresponding pointson minor lateral wall 5, thus resulting in translatory movement betweensuction cups 34 of portion 31 and minor lateral wall 5, which must becompensated by a like translatory movement of suction cups 34 withrespect to portion 31 in a direction perpendicular to axis 32 to avoidgenerating potentially harmful stress on minor lateral wall 5.

Actuating device 15 moves suction gripping head 14, engaging tubularpackage 3, into feed station 17, so as to align the open tubular package3 with insertion device 36. Since feed station 17 is located over pickupstation 11, the above transfer is made by a main movement in verticaldirection 20, by small adjusting movements in the other horizontaldirections 18 and 19, and by small rotations about axis 21.

Once tubular package 3 is aligned with insertion device 36, pusher 38 ofinsertion device 36 is moved to insert group 2 of cartons of cigarettesinside the open tubular package 3. Actuating device 15 then movessuction gripping head 14, engaging the open tubular package 3 containinggroup 2 of cartons of cigarettes, to feed tubular package 3 to sealingstation 16, by inserting the open tubular package 3 inside channel 43 ofconveyor 40. Once the open tubular package 3 containing group 2 ofcartons of cigarettes is engaged on opposite sides by suction belts 41of conveyor 40, suction head 14 releases tubular package 3 by cuttingoff suction through suction cups 34, and actuating device 15 is returnedto pickup station 11. To assist transfer of the open tubular package 3from gripping head 14 to conveyor 40, the bottom belt 41 of conveyor 40is longer than the top belt 41 of conveyor 40.

Conveyor 40 then feeds the open tubular package 3 inside channel 43, sothat the open tubular package 3 cooperates with sealing devices 45,which fold flaps 7 and 8 of tubular package 3 down one on top ofanother, and apply respective lengths of adhesive tape 10 to the foldedflaps 7 and 8. For which purpose, the open tubular package 3 is insertedinside channel 43 by gripping head 14, so that respective flaps 7 and 8project laterally from channel 43.

Finally, the sealed tubular package 3 is transferred from conveyor 40 toconveyor 46, and from this to the output station (not shown) and offboxing machine 1.

In an alternative embodiment shown by the dash line in FIGS. 2-5, afurther suction gripping head 47 is fitted to an arm 48 rotatedhorizontally by an actuating device 49 about a vertical axis 50.

In actual use, when suction gripping head 14 is moved over to pickupstation 11 to engage the top flat tubular package 3 in stack 13, arm 48is maintained by actuating device 49 in a rest position (not shown) toenable free vertical movement of suction gripping head 14, i.e. indirection 20.

Once suction gripping head 14, together with flat tubular package 3, ismoved by actuating device 15 from pickup station 11 to feed station 17,actuating device 49 rotates arm 48 about axis 50 to move suctiongripping head 47 into a work position (FIGS. 2-5) engaging the bottommajor lateral wall 4, i.e. the one opposite the major lateral wall 4engaged by suction gripping head 14. As of this position, tubularpackage 3 is converted from the flat to the open configuration byrotating portion 31 of suction gripping head 14 ninety degrees aboutaxis 32 with respect to portion 30 of suction gripping head 14, and alsoby means of a relative rotation movement between suction gripping head14 and suction gripping head 47, which is effected by keeping suctiongripping head 47 stationary, and moving suction gripping head 14 bymeans of actuating device 15.

Once tubular package 3 is in the open configuration, suction grippinghead 47 releases the bottom major lateral wall 4 of tubular package 3,and is restored by actuating device 49 to the rest position (not shown).

Using a further suction gripping head 47 as described above ensurescorrect opening, and safeguards against damage to, tubular packages 3 inany situation.

Boxing machine 1 as described above has countless advantages, by beingrelatively straightforward and compact, and by operating with stacks 13of flat tubular packages 3 which need not necessarily be positionedaccurately, and which can therefore be fed fully automatically.

1. A method of packing a product in a flat tubular package having twofirst lateral walls; and two second lateral walls, each connected on oneside to one first lateral wall, and on the other side to the other firstlateral wall, by respective preformed fold lines; the method comprisingthe steps of engaging a first lateral wall of the flat tubular packageand a second lateral wall of the flat tubular package by means of afirst portion and a second portion respectively of a first suctiongripping head, generating a rotational movement between the first andsecond portion of the first suction gripping head, to rotate the firstand second lateral wall engaged by the first suction gripping head withrespect to each other, and so convert the flat tubular package from theflat configuration to an open configuration, and inserting the productinside the open tubular package; wherein the first and second portion ofthe first suction gripping head are hinged and rotated about an axis ofrotation not coincident with the fold line between the first and secondlateral wall engaged by the first suction gripping head; wherein thefirst and second portion of the first suction gripping head compriserespective suction cups; and wherein the suction cups of the secondportion are fitted to the second portion to move in a directionperpendicular to the axis of rotation during the rotational movementbetween the first and second portion of the first suction gripping head.2. A method as claimed in claim 1, wherein the flat tubular package isengaged by the first suction gripping head at a pickup station, and istransferred, attached to the first suction gripping head, to a receivingstation where the product is inserted inside the open tubular package;the fiat tubular package being converted from the flat configuration tothe open configuration during transfer from the pickup station to thereceiving station.
 3. A method as claimed in claim 2, wherein, followinginsertion of the product inside the open tubular package, the firstsuction gripping head engaging the open tubular package is moved to feedthe open tubular package to a sealing station where the open tubularpackage containing the product is sealed.
 4. A method as claimed inclaim 3, wherein the first suction gripping head transfers the opentubular package to conveying means located at the sealing station andfor feeding the open tubular package through the sealing station and forfeeding the sealed tubular package to an output station.
 5. A method asclaimed in claim 3, wherein the open tubular package is sealed byfolding, one on top of another, flaps projecting from a first and asecond lateral walls of the tubular package, and by applying respectivelengths of adhesive tape to the folded flaps.
 6. A method as claimed inclaim 2, wherein, following insertion of the product inside the opentubular package, the open tubular package is sealed at the receivingstation, and the first suction gripping head engaging the scaled tubularpackage is moved to feed the sealed tubular package to an outputstation.
 7. A method as claimed in claim 1, wherein the flat tubularpackage is picked rip by the first suction gripping head off a stack offlat tubular packages.
 8. A method as claimed in claim 7 and comprisingthe further steps of determining, before engaging the top flat tubularpackage in the stack, the exact position of the flat tubular packageusing a sensor, and adapting the position of the first suction grippinghead according to the exact position of the flat tubular package so asto engage the flat tubular package in accordance with a given mutualarrangement.
 9. A method as claimed in claim 8, wherein the firstsuction gripping head is movable with four degrees of freedom comprisingthree translatory movements in three perpendicular directions, and onerotational movement about an axis perpendicular to the plane of the flattubular package.
 10. A method as claimed in claim 1, and comprising thestep of engaging, by means of a second suction gripping head, the firstlateral wall of the flat tubular package opposite the flu st lateralwall engaged by the first suction gripping head; the fiat tubularpackage being converted from the flat configuration to the openconfiguration by the rotational movement between the first and secondportion of the first suction gripping head, and also by a relativerotational movement between the first suction gripping head and thesecond suction gripping head.
 11. A method as claimed in claim 10,wherein, once the flat tubular package is converted to the openconfiguration, the second suction gripping head releases the firstlateral wall of the open tubular package.
 12. A method as claimed inclaim 10, wherein the second suction gripping head is rotated about avertical axis between a rest position allowing free vertical movement ofthe first suction gripping head, and a work position wherein the secondsuction gripping head engages the flat tubular package.
 13. A method asclaimed in claim 10, wherein the relative rotational movement betweenthe first suction gripping head and the second suction gripping head ismade by keeping the second suction gripping head stationary, and movingthe first suction gripping head.
 14. A method as claimed in claim 1,wherein the product is defined by a group of cartons of cigarettes. 15.A machine for packing a product in a flat tubular package having twofirst lateral walls; and two second lateral walls, each connected on oneside to one first lateral wall, and on the other side to the other firstlateral wall, by respective preformed fold lines; the machine comprisinga first suction gripping head having a first and a second portion, afirst actuating device for causing the first portion and the secondportion of the first suction gripping head to engage a first lateralwall of the flat tubular package and a second lateral wall of the fiattubular package respectively, actuating means for generating arotational movement between the first and second portion of the firstsuction gripping head, to rotate the first and second lateral wallengaged by the first suction gripping head with respect to each other,and so convert the flat tubular package from the flat configuration toan open configuration, and an insertion device for inserting the productinside the open tubular package; wherein the first and second portion ofthe first suction gripping head are hinged and rotated by the actuatingmeans about an axis of rotation not coincident with the fold linebetween the first and second lateral wall engaged by the first suctiongripping head; wherein the first and second portion of the first suctiongripping head comprise respective suction cups; and wherein the suctioncups of the second portion being are fitted to the second portion tomove in a direction perpendicular to the axis of rotation during therotational movement between the first and second portion of the firstsuction gripping head.
 16. A machine as claimed in claim 15, andcomprising a pickup station, where the flat tubular package is engagedby the first suction gripping head, and a receiving station; the firstactuating device moving the first suction gripping head attached to thefiat tubular package, from the pickup station to the receiving station;and the actuating means generating a rotational movement between thefirst and second portion of the first suction gripping head as the firstsuction gripping head is moved from the pickup station to the receivingstation.
 17. A machine as claimed in claim 16, wherein the pickupstation houses at least one stack of flat tubular packages, which areengaged successively by the first suction gripping head.
 18. A machineas claimed in claim 17, wherein the first suction gripping headcomprises a sensor for determining the exact position of the top flattubular package in the stack before the flat tubular package is engaged;a control unit being provided to control the first actuating devicesupporting the first suction gripping head so as to adapt the positionof the first suction gripping head to the exact position of the flattubular package, and engage the flat tubular package in accordance witha given mutual arrangement.
 19. A machine as claimed in claim 18,wherein the first actuating device moves the first suction gripping headwith four degrees of freedom comprising three translatory movements inthree perpendicular directions, and one rotational movement about anaxis perpendicular to the plane of the flat tubular package.
 20. Amachine as claimed claim 16, and comprising an output station; andconveying means for receiving the open tubular package containing theproduct from the first suction gripping head, and for feeding the opentubular package containing the product to the output station.
 21. Amachine as claimed in claim 20, and comprising sealing means for sealingthe open tubular package containing the product.
 22. A machine asclaimed in claim 21, wherein the sealing means are connected to theconveying means.
 23. A machine as claimed in claim 22, wherein thesealing means are located at the receiving station.
 24. A machine asclaimed in claim 20, wherein said conveying means comprise a first beltconveyor hinged to rotate about a horizontal axis between a horizontalposition, in which the first conveyor feeds the open tubular packagecontaining the product along a horizontal path, and a vertical position,in which the first conveyor feeds the open tubular package along avertical path.
 25. A machine as claimed in claim 24, wherein saidconveying means comprise a second belt conveyor aligned with the firstbelt conveyor when the first belt conveyor is in said vertical position.26. A machine as claimed in claim 15, wherein the insertion devicecomprises a conveyor for feeding the product into alignment with theopen tubular package; and a pusher for pushing the product inside theopen tubular package.
 27. A machine as claimed in claim 26, wherein theinsertion device comprises fixed sections for assisting insertion of theproduct inside the open tubular package.
 28. A machine as claimed inclaim 15, and comprising a second suction gripping head, and a secondactuating device for causing the second suction gripping head to engagethe first lateral wall of the flat tubular package opposite the firstlateral wall engaged by the first suction gripping head; the flattubular package being converted from the flat configuration to the openconfiguration by the rotational movement between the first and secondportion of the first suction gripping head, and also by a relativerotational movement between the first suction gripping head and thesecond suction gripping head.
 29. A machine as claimed in claim 28,wherein the second actuating device rotates the second suction grippinghead about a vertical axis between a rest position permitting freevertical movement of the first suction gripping head, and a workposition, in which the second suction gripping head engages the fiattubular package.
 30. A machine as claimed in claim 28, wherein therelative rotational movement between the first suction gripping head andthe second suction gripping head is generated solely by the firstactuating device.